Various medical devices interact with leads to assist with sensing, stimulating, or other functionality. For example, some implantable medical devices for treating irregular heart contractions, such as defibrillators and pacemakers, utilize transvenous leads for electrically stimulating the heart or for related sensing functions. According to some methods of transvenous lead implantation, one or more leads are introduced into a patient's vasculature at a venous access site. The leads are then deployed through the vasculature to a deployment site, for example in or near the heart.
Transvenous leads can contribute to partial or complete venous occlusion of the vasculature through which the leads are deployed. In fact, some evidence suggests that significant venous occlusion occurs in more than about 25% of patients. This interference with normal blood flow is undesirable, as it may result in arm pain and swelling, among other health problems. Occlusions also interfere with one or more of the ability to repair, add, remove, or replace leads. Furthermore, the presence of leads interferes with remedial measures for treating occlusions, such as the use of balloon catheters.